CSA and CSC in man and mammals to inhibit atherosclerosis and the recurrence of cardiovascular incidents in atherosclerotic mammals

ABSTRACT

This patent describes a method of treatment for inhibiting the development of atherosclerotic lesions in animals of the mammalian species including man, promoting the development of collateral circulation in regions of the heart supplied by the branches of coronary arteries, and inhibiting the occurrence of cardiac episodes including myocardial infarctions, acute coronary insufficiency and acute myocardial ischemia in human subjects with ischemic or coronary heart disease, which comprises the essentially regular and prolonged oral administration to mammals of a biologically and physiologically &#39;&#39;&#39;&#39;active&#39;&#39;&#39;&#39; chondroitin sulfate which is &#39;&#39;&#39;&#39;active&#39;&#39;&#39;&#39; chondroitin sulfate A, &#39;&#39;&#39;&#39;active&#39;&#39;&#39;&#39; chondroitin sulfate C, and mixtures thereof, said activity being manifested by at least an 80% prolongation of plasma thrombusformation time 6 to 12 hours after administration in rabbits as described in the Chandler loop method.

United States Patent [191 Morrison CSA AND CSC IN MAN AND MAMMALS TO INHIBIT ATHEROSCLEROSIS AND THE RECURRENCE 0F CARDIOVASCULAR INCIDENTS IN ATHEROSCLEROTIC MAMMALS [76] Inventor: Lester M. Morrison, Hollywood,

Calif.

[22] Filed: Jan. 17, I972 [21] App]. No.: 218,550

Related U.S. Application Data [63] Continuation-impart of Ser. No. 28,928, April 15, 1970, abandoned, which is a continuation-in-part of Ser. No. 606,020, Dec. 30, 1966, abandoned.

[52] U.S. Cl. 424/180 [51] Int. Cl. A61K 27/00 [58] Field of Search 424/180 [56] References Cited UNITED STATES PATENTS 1,950,100 3/1934 Crandell 424/183 3,405,120 10/1968 Kuwano 424/180 OTHER PUBLICATIONS Morrison (1), PSEBM Vol. 113, June 1963, page 362366. Morrison (2), Biol. Abst. Vol. 47, Dec. 15, 1966,

Abst. No. 116245. Morrison (3), PSEBM Vol. 123, Dec. 1966, pp.

[ 51 July 15,1975

Murata-Die Naturwiss Vol. 49, No. 2, Jan. 1962, pages 39-40.

Mansuke et al., Chem. Abst. V01. 65 (1966), page 2880a.

Matsuoka et al., Chem. Abst. Vol, 57, (1962), page l5745b.

Primary ExaminerSam Rosen Attorney, Agent, or FirmWills, Green & Mueth [57] ABSTRACT This patent describes a method of treatment for inhibiting the development of atherosclerotic lesions in animals of the mammalian species including man, promoting the development of collateral circulation in regions of the heart supplied by the branches of coronary arteries, and inhibiting the occurrence of cardiac episodes including myocardial infarctions, acute coronary insufficiency and acute myocardial ischemia in human subjects with ischemic or coronary heart disease, which comprises the essentially regular and prolonged oral administration to mammals of a biologically and physiologically active chondroitin sulfate which is active chondroitin sulfate A, active chondroitin sulfate C, and mixtures thereof, said activity being manifested by at least an 80% prolongation of plasma thrombusformation time 6 to 12 hours after administration in rabbits as described in the Chandler loop method.

9 Claims, No Drawings CSA AND CSC IN MAN AND MAMMALS TO INHIBIT ATHEROSCLEROSIS AND THE RECURRENCE OF CARDIOVASCULAR INCIDENTS IN ATHEROSCLEROTIC MAMMALS This application is a continuation-in-part of Ser. No. 28,928, filed Apr. 15, 1970, now abandoned, which application in turn was a continuation-in-part of Ser. No. 606,020, filed Dec. 30, 1966, and now abandoned.

Chondroitin sulfates A and C are widely distributed 1 in human and animal tissues, particularly in cartilage and other connective tissues, and although complexed with protein or peptide residues, the pure acid mucopolysaccharides can be isolated without undergoing appreciable degradation. Chondroitin sulfates A and C both contain D-glucuronic acid, 2-amino-2- deoxy-D-galactose and acetyl and sulfate residues in equimolar quantities. Structural investigations have shown that chondroitin sulfates A and C differ only in the position of the sulfate ester grouping in the hexosamine residue. Chondroitin sulfate A contains the repeating unit, 1 4)-O-B-D-glucopyranosyluronic acid-( l 3)-2-acetamido-2-deoxy-4-O-sulpho-B-D- galactopyranose, and chondroitin sulfate C the repeating unit, (I 4)-O-B-D-glucopyranosyluronic acidl 3 )-2-acetamido-2-deoxy-6-O-sulpho fi-D- galactopyranose. It has now been found that purified preparations of chondroitin sulfate A of apparently similar chemical composition as judged by ordinary methods of analysis may differ significantly in pharmacologic and physiologic activity. Similar findings were obtained in respect to purified preparations of chondroitin sulfate C.

The present invention is distinguished from the prior art in the following principal respects. First, until recently it was not appreciated that CSA and CSC could be obtained in a unique form which was active in preventing atherosclerosis and the recurrence of cardiovascular incidents in atherosclerotic mammals when administered on a regular basis over a prolonged period. This active material is to be contrasted with the material described in U.S. Pat. No. 3,405,120 which has been tested and found to be inactive in prolonging plasma thrombus-formation time 6 to 12 hours after administration in rabbits as described in the Chandler loop method and in preventing atherosclerosis in rats fed the atherogenic diet hereinafter described. In genera], the prior art as illustrated by U.S. Pat. No. 1,950,100 has contained no recognition of differences in the anti-atherosclerotic activity of different preparations of CSA and CSC of apparent similar chemical composition. This discovery of the present invention is believed to represent a major advance in the art.

Secondly, the present invention involves essentially regular and prolonged administration and, hence, is limited to more or less periodic administration on a daily basis over a period of at least several months and more typically, over a period of at least several years. Obviously, occasional interruptions in this program of administration are of no significance, so long as the program of administration is regular, viewed in the overall. Those skilled in the art will readily recognize the difference between essentially regular and prolonged usage as compared to erratic, occasional, or short term usage, the latter of which does not form any part of this invention.

SUMMARY OF THE INVENTION Briefly, the present invention comprises a method of treatment for inhibiting the development of atherosclerotic lesions in animals of the mammalian species including man, promoting the development of collateral circulation in regions of the heart supplied by the branches of coronary arteries, and inhibiting the occurrence of cardiac episodes including myocardial infarc- 0 tions, acute coronary insufficiency and acute myocardial ischemia in human subjects with ischemic heart disease, which comprises the essentially regular and prolonged oral administration to mammals of a biologically and physiologically active chondroitin sulfate which is active chondroitin sulfate A, active" chondroitin sulfate C, and mixtures thereof, said activity being manifested by a prolongation of plasma thrombus-formation time 6 to 12 hours after administration in rabbits as described in the Chandler loop method.

It is an object of this invention to inhibit the development of atherosclerotic lesions .in mammals.

It is another object to promote the development of collateral circulation in regions of the heart supplied by branches of coronary arteries.

Yet another object of this invention is to inhibit the occurrence of cardiac episodes such as myocardial infarctions, acute coronary insufficiency and acute myocardial ischemia in human subjects having ischemic or coronary heart disease.

These and other objects and advantages of this invention will be apparent from the following detailed description of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The treatment with CSA and CSC comprises the administration of the compound orally by the ingestion of 0.5 g. to 10 g. daily, usually one-third of the daily dosage being taken before or after each meal. The duration time of the treatment ranges from a short term (approximately 3 months) to continuous administration for the patients lifetime.

I have found that considerable variation exists in the plasma thrombus-formation time of different batches of chondroitin sulfate A 12 hours after intravenous administration despite the fact that on the basis of the following standard tests they are indistinguishable:

-Continued Test Method Range Methods of Enzymology. Volume lll. Edited by Sidney P. (olowick and Nathan 0. Kaplan. Academic Press. New York. 1957. pp. 93-101,

. "Optical density is determined at 420 my. on a Bcckmnn .lr. Model ll Spectrophotometerr None of the foregoing tests distinguish biologically and physiologically active CSA and biologically and physiologically active CSC from inactive material. The biological and physiological activity of the CSA and CSC can be determined as follows. When assayed for biologic and physiologic activity in prolonging plasma thrombus-formation time by the Chandler loop method as modified by Morrison et al. (J. Atheroscler. Res, 8:319, 1968), preparations of purified chondroitin sulfate A which were comparable as judged by the above Battery of tests resulted in the following average plasma thrombus-formation times of rabbits when assayed 12 hours post-injection:

Average plasma thrombusformation time 12 hours The tests were conducted with New Zealand white male rabbits ranging from 4 /2 to 5 /2 lbs. in body weight. The plasma thrombus-formation time was determined for each animal prior to injection and again 12 hours post-injection. The chondroitin sulfate A was dissolved in physiologic saline solution and diluted to a concentration of 80 mg/ml. The physiologic saline solution controls and the rabbits administered the chondroitin sulfate A solutions were administered the above solutions intravenously in the ear vein at a level of 1 ml per kg of body weight. A minimum of six rabbits was employed in each group. Injections of physiologic sathrombus-formation times over pre-injection levels when blood samples were taken 12 hours after injection. As indicated in the above table, however, a number of chondroitin sulfate A preparations resulted in a highly significant increase in plasma thrombusformation times 12 hours post-injection over that of saline-injected controls whereas others had little if any activity in this regard. It is of interest that heparin which is extremely active inprolonging plasma thrombus-formation time in blood samples taken minutes after intravenous injection does not result in a prolongation of plasma thrombus-formation time in blood samples taken 6 to 12 hours after injection. Samples of chondroitin sulfate A which result in a marked prolongation of plasma thrombus-formation time in blood samples taken 12 hours after injection were found, however, to have no significant effect in prolonging plasma thrombus-formation time over pro-injection levels in blood samples taken 15 minutes after injec-' tion.

line solution caused no significant change in plasma it has also been found that in the case of chondroitin sulfate C purified preparations of this material which were similar on the basis of the chemical tests indicated above varied markedly in activity in prolonging the plasma thrombus-formation time of rabbits in blood samples taken 12 hours post-injection.

in general, preparations of purified chondroitin sulfate A. purified chondroitin sulfate C, or combinations of the two which result in at least an increase in the plasma thrombus-formation time of rabbits 12 hours post-injection under the conditions indicated above compared to values in saline-injected controls are active in inhibiting or preventing the occurrence of atherosclerosis. No claim is made that the plasma thrombus-prolonging activity of such preparations following intravenous administration is related to the antiatherogenic activity obtained following oral administration. The thrombus-prolonging assay is merely used as a screening device for detecting preparations with anti-atherogenic activity. It has been observed that every preparation of purified chondroitin sulfate A or C or combinations of the two that had anti-atherogenic activity under the conditions indicated below were also active in prolonging the plasma thrombus-formation time of rabbits 12 hours post-injection by a value at least 80% greater than that of saline-injected controls. Findings also indicate that preparations that were most active in prolonging the plasma thrombus-formation time of rabbits under the above test conditions were also the most active in anti-atherogenic activity. in contrast, preparations of purified chondroitin sulfate A and/or C that had little if any anti-atherogenic activity were invariably those that failed to prolong the plasma thrombus-formation time of rabbits to a significant degree over that of saline-injected controls under the conditions indicated above.

Differences in the activity of different preparations of purified chondroitin sulfate A and C can result both from differences in the method of preparation and differences in the starting material. 1 have observed that samples of purified chondroitin sulfate A prepared from the same starting material differed significantly in respect to their effect on plasma thrombus-formation time 12 hours post-injection depending on the method employed in preparing chondroitin sulfate A. I have also observed that methods that resulted in highly active materials by the above assay procedure when applied to some starting materials resulted in inactive preparations when applied to other starting materials, despite the fact that differences in the various preparations could not be demonstrated by the battery of chemical tests indicated above.

An experimental model for the induction of atherosclerosis in the aorta and coronary arteries of rats has been developed and consists of feeding young rats for 6 weeks a purified, cholesterol-containing diet supplernented with 1.25 million U.S.P. units of vitamin D (Viosterol) per kg of ration. Rats fed a similar diet with either cholesterol or the 1.25 million U.S.P. units of vitamin D omitted, did not show such lesions. The distribution and microscopic appearance of such lesions is very similar to that observed in human subjects with atherosclerotic lesions in these tissues. it has been found that the oral administration of purified preparations of chondroitin sulfate A and C or combinations of the two which are active in prolonging the plasma thrombus-formation time of rabbits as indicated above are highly active in reducing or preventing the occurrence of atherosclerotic lesions on the atherogenic diet indicated above.

The following provides a description of the experi- 0.5% cholic acid 1.25 million U.S.P. units of vitamin D per kg of diet; Group V was fed the same diet as group IV but in addition received a supplement of 1% purified chondroitin sulfate A (lot No. 9008). The

mental conditions employed in inducing atherosclcr- 5 test supplements were incorporated in the basal ration osis and the results obtained with a biologically and in place of an equal amount of sucrose. Animals were physiologically active preparation of purified chonkept in metal cages with raised screen bottoms (three dr n ulfat rats per cage) and were provided the various diets and The basal ration employed was a highly purified diet water ad libitum. The animals were fed daily and all consisting of sucrose, 61%; Vitamin-Free Test Casein, food not consumed 24 hours after feeding wa di 24%; cottonseed oil. 10%; Hubbell, Mendel and Wakecarded. The rats were weighed weekly during the man Salt Mixture. 5%; and the following vitamins per course f the experiment. kg. of diet: thiamine hydrochloride, 10 mg; riboflavin, 10 mg; pyridoxine hydrocmoridfiv 10 mg; calcium Pam After weeks of feed ng, the rats were anesthetized tothenate, 60 mg; nicotinic acid, 100 mg; ascorbic acid, Wlth Sodlum bloofj was Yvlthdrawn 200 mg; biotin 1 mg; folic acid, 10 mg; paraaminobfim from the heart into a heparmized syringe. L vers were ZOic acid 200 mg; inositol 400 mg; vitamin B12, 150 excised blotted to remove excess blood, weighed and micrograms; 2 methy] lAmaPhthoCuinone 5 mg; stored in freezer until anaylyed. Lipid was extracted line chloride. 2 gm; vitamin A, 5,000 U.S.P. units; vitafrom thfaflhvers by the method of Thompson et (Brit min D 500 U.S.P. units; and alpha-tocopherol acetate, Numnon 3: 9 1949): and total and free f lO0 mg The vitamins were added in place of an equal terol were determined on liver and plasma by a modifiamount of sucrose. Fifty-four male rats of the Long- Canon of the ,method of schoenlielmer and Sperry as Evans Strain averaging 145 gm in body weight (range reported by Nieft and Deuel (J. Biol. Chem, 177: 143, 136 to 155 gm) and 54 female rats of the Long-Evans 1949) At necropsy h hearts and aorta fixefj m Strain averaging 146 gm in body weight (range 138 to 10% buffered formalin. The hearts were divided into 156 gm) were selected for the following experiment: thre? parts conslstmg of the apex mlddle and basal Animals were divided into five groups of comparable porno; and h aortas. were cut transversly at the weight. Groups 1, I1 and 111 consisted of six animals of arch and the mld'thoraclc level Segue of the each sex; groups 1V and V consisted of 18 animals of above w l f Cut at 16*20 mlcra m thufkness each sex. Group 1 was fed the basal ration indicated a Stamed wlth l' 'Q for the demfnstramn of above; group H was fed the basal ration +1670 purified lipid and counterstamed with hematoxylm. Ten cross chondroitin sulfate A (lot No. 9008). The latter prepa- Sectlons were prepared through eac h part 9 the heart ration resulted in a plasma thrombus-formation time of and thmugh the arch and ,thoraclc pomolls of the 48.8 minutes 12 hours post-injection in rabbits in conaorta The Shdes W exammed und er a mlcroscope mist to an average thrombus formation time of 132 and graded for the incidence and seventy ofatheroscleminutes in saline-injected controls, when tested under leslons' the conditions described previously. Group 111 was fed The incidence and distribution of atherosclerotic 1ethe basal ration 1.5% cholesterol 0.5% cholic acid. sions in the coronary arteries and aorta of rats in the Group [V was fed the basal ration 1.5% cholesterol 40 various groups are summarized in Table 1.

Table I Effects of an active" chondroitin sulfate A preparation on the incidence and distribution of atherosclerotic lesions in the coronary arteries and aorta of rats fed a hypervitaminosis D atherogenic diet.

Non-Atherogenic Diets Atherogenic Diets Group I Group 11 Group 111 Group IV Group V Male rats Number of animals per group 6 6 6 18 18 Initial body weight, gm. 145.3 145.3 145.3 145.6 1456 Final body weight", gm. 362.0 365.7 371.5 131.1 158.9 Histological findings Coronary atherosclerosis incidence. 0.0 0.0 0.0 100.0 16.7 Average number of arteries affected per rat in following parts of heart:

Basal 0.0 0.0 0.0 4.2 05 Middle 00 0.0 0.0 3.5 0.1 Apical 0.0 0.0 0.0 2.4 0.2 Aortic atherosclerosis lncidence, 0.0 0.0 0.0 94,4 0,0 Percentage of animals per group showing lesions in the following parts of the aorta and score per affected rat:

lntracardiac 0.0 0.0 0.0 44.4 0

2 Arch 0.0 0.0 0.0 88.9 0.0

(2.1 Mid thoracic 0.0 0.0 0.0 66.7 0.0

Female rats Number of animals per group 6 6 6 18 18 Initial body weight. gm. 146.5 146.5 146.5 146.5 146.5 240.8 229.3 259.6 110.3 138.2

Final body weight*, gm.

Table l-Continucd Effects of an active chondroitin sulfate A preparation on the incidence and distribution of atherosclerotic lesions in the coronary arteries and aorta of rats fed a hypervitaminosis D atherogenic diet.

Non-Atherogenic Diets Atherogenic Diets Group I Group ll Group III Group IV Group V Histological findings Cornary atherosclerosis incidence. 0.0 0.0 0.0 lO0.00*** 16.7 Average number of arteries affected per rat in following parts of the heart:

Basal 0.0 0.0 0.0 2.7 0.2 Middle 0.0 0.0 0.0.- 2.8 0:1 Apical 0.0 0.0 0.0 2.7 0.0 Aortic atherosclerosis Incidence, 0.0 0.0 0.0 l00.0*** 27.8 Percenta e of animals er group showing esions in the ollowing parts of the aorta and score per affected rat:

lntracardiac 0.0 0.0 0.0 87.5 27.8

' (2.0)** (1.2)" Arch 0.0 0.0 00 I000 4 (2.7)** (l.2)** Mid thoracic 0.0 0.0 0.0 93.8 1 1.1

The experiment was terminated after 6 weeks of feeding. "The severity of lesions was evaluatedon the basis of a scale ranging from 0 to 4.

'"Two of the rats in this group died during the course of the experiment. Data in this group are based on.the surviving 16 animals in thisgroupr Findings indicate that the oral administration ofa biologically active" preparation of chondroitin sulfate A at a 1% level in the diet caused a highly significant reduction in the incidence and severity of atherosclerotic lesions in the coronary arteries and aorta of rats fed a hypervitaminosis D atherogenic diet. Additional studies conducted with a biologically active preparation of chondroitin sulfate C indicate that the latter material was similarly active in this regard. In contrast, preparations of purified chondroitin sulfate A and C which were similar to the above preparations in respect to chemical composition by the tests indicated previously but which were inactive" in respect to prolonging the plasma thrombus-formation time of rabbits as determined by the Chandler loop method in blood samples taken 12 hours post-injection, such samples had little if any activity in reducing the incidence and severity of atherogenic lesions under the test conditions indicated above.

An additional finding and one that appears to be 45 unique in respect to forms of medication attributed to have anti-atherogenic activity is that the antiatherosclerotic activity of active preparations of chondroitin sulfate A and C is not associated with any detectable effect of these preparations in lowering of 50 plasma and liver cholesterol and liver total lipid levels. The increase in plasma and liver cholesterol and liver total lipids in rats fed the hypervitaminosis D atherogenic diet supplemented with 1% of an active preparation of chondroitin sulfate A or C was just as marked in rats fed the latter supplements comparedto that of rats fed the basal non-atherogenic diet as it was in rats fed the atherogenic diet with the chondroitin sulfate A andComitted. I x .The effectiveness of biologically active" preparations of chondroitin sulfate A and C in promoting the development of collateral circulation in regions of the heart supplied by branches of the coronary arteries is shown by the following data. v i Rats were fed the atherogenic diet (group IV) indicated above (i.e., the basal ration supplemented with 1.5% cholesterol, 0.5% cholic acid and 1.25 million U.S.P. units of vitamin D per kg of diet). These rats showed a significant reduction in the number of branch coronary arteries as determined by actual count of the branch coronary arteries in cross-sections in all three parts of the heart (i.e., basal, middle and apical portions) compared to'that of rats fed the non-atherog'enic diets (groups I, II and 'III). This effect pertained to the branch coronary arteries not the main coronary arteries. When rats were fed the atherogenic diet indicated above but in addition were fed an factivepreparation of chondroitin sulfate A at a 1% levelin the diet (group V), the number of branch coronary arteries was increased to levels approaching that of rats fed the nonatherogenic diets (groups I, II and Ill). Similar findings were observed in both male and female rats. Results are summarized in Table II below.

Table II Effects of an active" chondroitin sulfate A preparation on the number of branch coronary arteries of rats fed a hypervitaminosis D, atherogenic diet.*

Dietary group No. of Animals Average number of coronary arteries per cross per group section in following pans of the heart:

Basal section Middle section Apical section Main Branches Main Branches Main Branches Male rats Non-atherogenic diets Group I 6 4.7 25.3 6.0 31.6 3.8 26.0

Group ll 6 5.3 28.2 6.5 33.0 4.5 28.0

Group III 6 3.5 23.0 5.0 27.5 3.8 23.0 Atherogenic diets Group IV 8 3.7 l4.8 5.5 20.0 3.3 l5.6

Group V 8 4.8 20.9 5.7 Y I 27.3 3.6 22.8

Effects of an "active chondroitin sulfate A preparation on the number of branch coronary arteries of rats fed a hypervitaminosis D. atherogenic diet.*

Dietary group No. of Animals Average number of coronary arteries per cross per group section in following parts of the heart:

Basal section Middle section Apical section Main Branches Main Branches Main Branches Female rats Non-atherogenic diets Group 1 6 5.2 20.0 5.2 28.3 4.2 25.3 Group 11 6 4.0 25.3 5.7 32.5 3.3 26.2 Group 111 6 4.3 27.7 5.0 30.0 4.0 25.5 Atherogenic diets Group IV 18 3.2 11.7 4.8 18.0 3.2 14.5 Group V 18 4.0 21.4 5.6 29.1 4.1 22.1

The experiment was terminated after 6 weeks of feeding.

and twenty patients with ischemic coronary disease as determined by electrocardiograms plus clinical history including angina pectoris and/or past myocardial infarctions, who had been treated for these conditions during periods varying from 6 months to 20 years, were divided into two groups of 60 patients each, matched as closely as possible for age, sex, and clinical and laboratory findings. A comparison of the two groups is given in Table 111.

Both groups of patients were randomly selected as they Table 111 Condition of 60 CSA-Treated lschemic Coronary Disease Patients and 60 Control Patients Prior to study PREVIOUS RECEIVING TOTAL AVERAGE MYOCAR- ANTl- NO. OF

DIAL COAGULANT AGE ANGlNA lNFARC- HYPERTEN- THERAPY PATIENTS TION SlON (years) (No.) (No.) (No.) (No.) (No.) MALES:

CSA 66 15 7 6 6 16 Controls 66 I9 12 8 7 25 FEMALES:

CSA 64 25 6 2O 3 44 Controls 67 20 3 l9 3 ALL:

CSA 65 4O 13 26 9 6O Controls 66 39 15 27 1O 60 appear that active preparations of chondroitin sulfate A would be active in promoting the development of collateral circulation in regions of the heart supplied by branches of the coronary arteries. Additional studies indicate that active preparations of chondroitin sulfate C were similarly active in this regard whereas preparations of purified chondroitin sulfate A and C that were inactive in prolonging the plasma thrombusformation time of rabbits under the test conditions indicated previously were without activity in preventing the reduction in the number of branch coronary arteries of rats fed a hypervitaminosis D, atherogenic diet.

The effectiveness of active preparations of chondroitin sulfate Aand C in preventing the occurrence of cardiac episodes (including myocardial infarctions, acute coronary insufficiency and acute myocardial ischemia) in human subjects with ischemic coronary heart disease is shown by the following results.

The term ischemic coronary disease" (1CD) as employed herein describes insufficiency of blood flow to the myocardium. lt denotes not only the presence of coronary artery disease (silent" atherosclerosis involves the coronary arteries in the majority of North American adults) but progression of the atherosclerosis process to the stage ofa clinically and/or electrocardiographically demonstrable abnormality. One hundred presented themselves in clinical practice in alternate fashion. All pre-test comprehensive therapeutic regimens were continued or expanded. lncluded were lowsodium, low-cholesterol diets, restricted sugar intake where indicated, coronary artery, cerebral artery or peripheral artery vasodilators, sedatives, oral anticoagulants, vitamin and/or nutritional supplements (including highly unsaturated oils and fats), thyroid extract and female sex hormones. The two groups differed in only one respect. Subject in group 11 were administered an active preparation of chondroitin sulfate A daily. Those in group lwere not. During the first year of the study subjects in group 11 were given 1.5 to 10 gm of an active chondroitin sulfate A preparation daily, initially in powder form, and later in the form of tablets containing 0.5 gm of purified chondroitin sulfate A per tablet. During the second and third years of the study the dosage of active chondroitin sulfate A administered was either 1.5 gm or 3 gms per day in tablet form.

The chondroitin sulfate A was prepared from bovine tracheal cartilage. Each batch of chondroitin sulfate A was tested for plasma thrombus-prolongation activity as indicated previously and only those preparations which were active" as judged by this bioassy procedure were employed for test purposes.

Laboratory test for the hemopoietic, hepatic, renal and other systems were made in both groups of patients and in group II these tests were usually conducted every 1 to 2 months over the first 2-year period, then every 4 months during the third year of the treatment study period. These tests were: complete blood count, sedimentation rate, urinalysis, protein bound iodine, I labeled triiodothyronine, sodium, potassium, thymol turbidity, serum glutamic oxalacetic transaminase, serum glutamic pyruvic transaminase, serum bilirubin direct and indirect, calcium. phosphorus, creatinine, glucose, total protein, albumin, globulin, urea nitrogen, uric acid, alkaline phosphatase, cephalin flocculation, cholesterol and beta-lipoprotein.

In addition, chest x-rays and resting electrocardiograms were made in each patient; Master exercise electrfocardiograms were taken in most patients, ophthamlrnologic examinations were conducted by qualified ophthalmologists in all cases; photographs of the microcirculation in the conjunctiva] vessels were made in 27 patients.

Coronary risk factors such as obesity, hypercholesteremia, hyperlipema, hyperbetalipoproteinemia, hypertension, tobacco intake, diabetes mellitus were of approximately equal incidence in both groups of patients, with no preponderance of any of theabove factors having been noted in either group.

No deleterious effects attributed to chondroitin sulfate A administration either clinically or on the basis of laboratory findings were observed in any of the subjects over the 3-year period of observation.

Table [V indicates details of mortality and morbidity in the 120 patients studied over the 3-year period of in- 12 acute coronary insufficiency or impending myocardial infarction, each patient was first admitted and treated in an acute coronary care unit of a general hospital. Of the 6 fatal myocardial infarction cases, 4 were 5 males aged 76, 71, 65 and 56 respectively; the two fatal myocardial infarction female patients were aged 65 and .79 respectively. Three patients died during the first year of observation, the others died during the remaining 2 years of observation and treatment of the general therapeutic regime described above. Of the 6 cases of myocardial infarction (fatal), 4 patients had a history of chronic angina pectoris.

There were 8 patients who survived myocardial infarctions, 2 of these having two incidents each, so that there were 10 incidents of non-fatal myocardial infarction. Of these 8 patients, 5 were males and 3 were females. Their ages rangedfrom 49 years to 83 years, with an average of 68 years. None received anticoagulant therapy prior to the attack. Five patients had a previous myocardial infarction.

There were 8 incidents (7 patients, 1 twice) of acute coronary insufficiency. All of these patients were admitted to the acute coronary care units of hospitals, some with the admitting physicians diagnoses of threatened or impeding myocardial infarction, of protracted angina pectoris or status anginosus. All

7 patients recovered from the acute coronary insufficiency, but 2 patients subsequently suffered massive myocardial infarctions, one 12 months later (non-fatal) and the other 21 months later (fatal). The former of these 2 patients was hospitalized twice for acute coronary insufficiency.

vestigation. Five patients with myocardial ischemia were hospi- Table IV Acute Cardiac Incidents Occurring in 60 CSA-Treated Patients and 60 Control Patients I with Ischemic Coronary Disease During a Three-Year Study Period ACUTE MYOCAR INFARCT IONS CORONARY MYOCAR- DIAL DIAL FATAL NON-FATAL INSUFFI- ISCHEMIA TOTAL CIENCY* MALE:

CSA 2 O O 0 2 Controls 4 6 4 0 l4 FEMALE:

CSA l 0 1+ 0 2 Controls 2 4 4 5 -'l5 ALL:

CSA 3 0 1+ 0 4 Controls 6 8 5 29 Hospitalized "Hospitalized and transient +Fatal In Group I of the 60 patients who did not receive CSA the following acute cardiac incidents occurred: 1. Myocardial lnfarctions fatal 6 incidents 2. Myocardial Infarctions non-fatal 10 incidents I 3. Acute Coronary Insufficiency or Acute Myocardial Ischemia (non-fatal) 8 incidents 4. Myocardial ischemia (non-fatal) 5 incidents All patients listed above were hospitalized with the exception of two fatal cases of myocardial infarction who were diagnosed by an attending physician other than the author and described as such on death certificates. In the patients diagnosed in the hospital as talized for distressing symptoms referable to their cardiovascular system. However, these were not sufficiently severe and the ECG and blood enzyme changes were not critical enough to required admission to an acute coronary care unit; these patients were consequently kept on the general hospital patient car services for treatment. All five patients were females; ages ranged from years to 75 years, with an average of 65 years.

In' Group II, of the CHD patients ,who received active CSA the following acute cardiac incidents occurred:

l. Myocardial Infarction fatal 3 incidents 2. Myocardial Infarction non-fatal incidents 3. Acute Coronary Insufficiency (terminal) l incident 4. Myocardial lschemia 0 incidents Two of the fatal myocardial infarction patients were males and the third was a female, at ages 68, 77 and 65 respectively.

In the first fatal myocardial infarction patient, in whom an autopsy was performed, CSA had been discontinued for 2 months prior to death. The second patient in this category had taken CSA intermittently for 1 year, then had discontinued it for 1 year prior to death. The third patient (female) who suffered a fatal myocardial infarction had persistent hypertension which frequently was difficult or impossible to control. In the female patient who died with a terminal coronary insufficiency and cardiac congestive failure, these were the terminal complications following a massivecerebrovascular hemorrhage in a patient with chronic fibrillation and flutter. Three of these four patients had a history of chronic angina pectoris Some patients in the CSA treated group underwent frequent periods of brief interruption of CSA medication, due to shortages of supply, intermittent upper respiratory or gastrointestinal influenzal infections or food upset episodes. These were of short duration, lasting from several days to at most several weeks.

To date no other cardiac incidents have occurred in the 60 CSA treated patients other than the above 4 patients. Strictly speaking, two of these four patients might not be considered valid cases of failure of CSA to prevent an acute cardiac accident since in one incident (fatal myocardial infarction in the 77 year old male) the patient had discontinued taking CSA 1 year prior to death and in a second. the patient actually expired from a massive cerebrovascular accident in which the cardiac failure occurred as a complicating terminal event.

One other patient in this group was lost due to death; autopsy revealed a malignant cerebral astrocytoma in a female patient aged 62. This patient already had cerebral symptoms when CSA therapy was begun, having undergone two hospital admissions for diagnostic cerebral and general neurologic examinations. These failed to disclose the cerebral lesion which was revealed subsequently at pre-mortem surgery and autopsy.

In the 60 control patients, there was a total of 29 cardiac incidents over the 3-year period of observation in contrast to a total of 4 cardiac incidents in a comparable group of patients administered daily oral doses of an active" preparation of chondroitin sulfate A.

PREPARATION OF ACTIVE CSA One starting material for the preparation of active chondroitin sulfate A is bovine trachea. This material is obtained from the slaughter houses as soon as possible after the animals are slaughtered. It is then frozen until processed. In processing, it is trimmed free of tissue and finely ground. This ground tissue is defatted with five parts of acetone. Two extractions are made to reduce the fat content to approximately 1% or less. The defatted material is dried and re-ground. A solution of the latter is made up in a 0.1 M calcium acetate buffer containing l% papain plus 0.005 M cystein hydrochloride and 0.005 M disodium versenate as enzyme activators. The entire mixture is maintained at 62C *3 3C for 24 to 30 hours with gentle stirring. Approximately to solubilization of the trachea is obtained. This supernatant is decanted and is precipitated with two volumes of acetone. The acetone supernatant is decanted. The remaining precipitated material is dissolved in isotonic saline to make a solution of 35%. To the latter is added a saturated solution of potassium permanganate in 2 to 5 ml. portions with constant stirring. adding each portion until the purple color has been totally discharged. Depending on the various raw materials started with, this may take anywhere from 50 to 200 ml. of potassium permanganate solution per 6 lbs. of starting raw material. When at the interval between addition and discharge, the color becomes long (sic) (more than 5 minutes), no further permanganate is added. The solution is then allowed to stand overnight to permit flocculation of the manganese dioxide and completion of any reactions. The manganese dioxide is removed either by centrifugation or filtration through a coarse filter paper. The maganese dioxide cake is washed with additional isotonic saline. In some cases the addition of a small amount of formaldehyde or methanol will cause flocculation of manganese dioxide which is then precipitated with one volume of acetone. The resultant oily precipitate is collected by decantation, the solvent evaporated or the cake dissolved in a minimum amount of water and the final product obtained by lyophilization. It appears on paper chromatography to be essentially pure chondroitin sulfate A. Analysis of the product shows a typical chondroitin sulfate A infra-red spectrophotometric absorption curve. Optical rotation determinations give values of (a),, 24; nitrogen content, 3.3%.

PREPARATION OF ACTIVE CSC One starting material for the preparation of active chondroitin sulfate C is shark cartilage. This material obtained in a dry form is ground and defatted with three to five parts acetone. On extraction is usually sufficient. This extracted shark cartilage is then treated as indicated above for the dried bovine trachea after the defatting stage.

Having fully described the invention, it is intended that it be limited only by the lawful scope of the appended claims.

I claim:

I. The method of treatment for inhibiting the development of atherosclerotic lesions in animals of the mammalian species, promoting the development of collateral circulation in regions of the heart supplied by the branches of coronary arteries, and inhibiting the occurrence of cardiac episodes including myocardial infarctions, acute coronary insufficiency with acute myocardial ischemia in human subjects with ischemic heart disease, which comprises the essentially regular and prolonged oral administration to mammals of an effective amount of a biologically and physiologically active chondroitin sulfate A, active chondroitin sulfate C, or mixtures thereof, said activity being manifested by at least an 80% prolongation of plasma thrombus-formation time 6 to 12 hours after administration in rabbits as described in the Chandler loop method.

2. The method of claim 1 wherein the active" chondroitin sulfate A is prepared from ground bovine trachea by:

l. treating a solution of the defatted and finely divided tissue with a papain enzyme to solubilize the bulk of the tissue, 1

2. precipitating the solubilized material with acetone,

3. contacting the precipitate solubilized in an aqueous solution with a permanganate oxidizing agent,

' 4.recovering essentially pure active 'chondroitin sulfate A.

3. The method of claim 2 wherein the essentially pure CSA is recovered by evaporation.

4. The method of claim 2 wherein the essentially pure CSA is recovered by. lyophilization.

5. The method of claim 1 wherein the active. chondroitin sulfate C is prepared from ground shark cartilage by: I

l. treating a solution of the defatted and finely di vided tissue with a papain enzyme to solubilize the bulk of the tissue,

2. precipitating the solubilized material with acetone,

3. contacting the precipitate solubilized in an aqueous solution with permanganate oxidizing agent, and

4. recovering essentially pure active chondroitin sulfate C V v i 6. Themethod of claim 5 wherein the essentially pure CSC is recovered ,by evaporation.

7. The method of claim 5 wherein the essentially pure CSC is recovered by lyophilization.

8. The method of claim 1 wherein the drug is orally ingested in an amount of about 0.5 to 10 grams daily. 9. The method of treatment for inhibiting the development of atherosclerotic lesions in humans, promoting the development of collateral circulation in regions of the heart supplied by the branches of the coronary arteries, and inhibiting the occurrence of cardiac episodes including myocardial infarctions, acute coronary insufficiency and acute myocardial ischemia in human subjects with ischemic heart disease, which comprises the essentially regular and prolonged oral administration to human subjects of an effective amount of a biologically and physiologically active chondroi tin sulfate A, active chondroitin sulfate C, or mixtures thereof, said activity being manifested by ,at least an prolongation of plasma thrombus-formation time 6 to 12 hours after administration in rabbits as described in the Chandler loop method. 

1. THE METHOD OF TREATMENT FOR INHIBITING THE DEVELOPMENT OF ATHEROSCLEROTIC LESIONS IN ANIMALS OF THE MAMMALIAN SPECIES, PROMOTING THE DEVELOPMENT OF COLLATERAL CIRCULATION IN REGIONS OF THE HEART SUPPLIED BY THE BRANCHES OF CORONARY ARTERIES, AND INHIBITING THE OCCURRENCE OF CARDIAC EPISODES INCLUDING MYOCARDIAL INFARCTIONS, ACUTE CORONARY INSUFFICIENCY WITH ACUTE MYOCARDIAL ISCHEMIA IN HUMAN SUBJECTS WITH ISCHEMIC HEART DISEASE, WHICH COMPRISES THE ESSENTIALLY REGULAR AND PROLONGED ORAL ADMINISTRATION TO MAMMALS OF AN EFFECTIVE AMOUNT OF A BIOLOGICALLY AND PHYCIOLOGICALLY "ACTIVE" CHONDROITIN SULFATE A, "ACTIVE" CHONDROITIN SULFATE C, OR MIXTURES THEREOF, SAID ACTIVITY BEING MANIFESTED BY AT LEAST AN 80% PROLONGATION OF PLASMA THROMBUS-FORMATION TIME 6 TO 12 HOURS AFTER ADMINISTRATION IN RABBITS AS DESCRIBED IN THE CHANDLER LOOP METHOD.
 2. The method of claim 1 wherein the ''''active'''' chondroitin sulfate A is prepared from ground bovine trachea by:
 2. precipitating the solubilized material with acetone,
 2. precipitating the solubilized material with acetone,
 3. contacting the precipitate solubilized in an aqueous solution with permanganate oxidizing agent, and
 3. contacting the precipitate solubilized in an aqueous solution with a permanganate oxidizing agent, and
 3. The method of claim 2 wherein the essentially pure CSA is recovered by evaporation.
 4. The method of claim 2 wherein the essentially pure CSA is recovered by lyophilization.
 4. recovering essentially pure active chondroitin sulfate C.
 4. recovering essentially pure active chondroitin sulfate A.
 5. The method of claim 1 wherein the ''''active'''' chondroitin sulfate C is prepared from ground shark cartilage by:
 6. The method of claim 5 wherein the essentially pure CSC is recovered by evaporation.
 7. The method of claim 5 wherein the essentially pure CSC is recovered by lyophilization.
 8. The method of claim 1 wherein the drug is orally ingested in an amount of about 0.5 to 10 grams daily.
 9. The method of treatment for inhibiting the development of atherosclerotic lesions in humans, promoting the development of collateral circulation in regions of the heart supplied by the branches of the coronary arteries, and inhibiting the occurrence of cardiac episodes including myocardial infarctions, acute coronary insufficiency and acute myocardial ischemia in human subjects with ischemic heart disease, which comprises the essentially regular and prolonged oral administration to human subjects of an effective amount of a biologically and physiologically ''''active'''' chondroitin sulfate A, ''''active'''' chondroitin sulfate C, or mixtures thereof, said activity being manifested by at least an 80% prolongation of plasma thrombus-formation time 6 to 12 hours after administration in rabbits as described in the Chandler loop method. 